The signal’s always green for a few city government drivers who’ve piled up tens of thousands of dollars in overtime pay – nearly doubling their base salaries, The Post has found.

The leader of the pack was Robert Macko, who chauffeured Brooklyn Borough President Marty Markowitz to what was described as a dizzying array of official events.

Macko pulled down $79,475 last year on a base of $45,000.

A Markowitz spokeswoman said the $34,475 OT bonanza was a fluke.

“The borough president has an extremely hectic schedule whose hours are normally shared among three drivers,” explained Jocelyn Aframe.

She said one of the drivers was injured, went on worker’s compensation and couldn’t be replaced until he was off the Borough Hall payroll.

As a result, “the remaining drivers worked hard to cover the hours,” Aframe said, adding that the situation has since been remedied.

She also said Macko’s salary for most of fiscal 2004 was $40,000, not the $45,000 recorded in city records.

A second Markowitz driver, Altay Karabay, collected $7,559 in overtime on a base of $40,000.

Markowitz is apparently much busier than any of the other four borough presidents.

Not one paid a cent in OT to their drivers, according to records provided to The Post under the Freedom of Information Law.

Freddy Patterson, who wheels around City Planning chair Amanda Burden, was another driver in the dough.

He boosted his $40,902 salary to $73,259, city records show.

A spokeswoman defended the expenditure, saying Burden oversees “an extremely ambitious work plan” and “personally visits proposed rezoning areas and attends many community meetings throughout the city from early morning to late evening.”

A half-dozen drivers at the Department of Homeless Services broke the $55,000 earnings mark, including one who more than doubled his salary.

Robert Mascali, an agency spokesman, said the drivers transport clients in an around-the-clock operation that witnessed record demand last year.

“They’re not driving around any staff people,” he said.

Government watchdog Henry Stern called the OT expenditures a waste.

“This is an example of expenses getting out of control,” said Stern, a former Parks commissioner.